Explanation of abbreviations A-CDM

Explanation of abbreviations below is simplified, describes usual sitiuation and most common operational environment. It doesn’t take into account exceptions that are exempt from A-CDM procedures.

• FPL = Flight Plan - ICAO flight plan. Standard form:
• FPL ID = Flight PLan IDentificator – Unique identificator of a particular flight plan related to a particular flight. 
• SOBT – Scheduled Off-Block Time is a time, when commencing taxi (or pushback) is planned. It is equal to airport departure slot (for regular flights usually also to published flight schedule). LKPR is a coordinated airport, therefore every departure must have allocated departure slot. Departure slot can be obtained from slot coordinator. Exact procedure how to request for SOBT can be found on coordinator’s webpage or in a corresponding part of AIP ČR.

Without approved allocated SOBT the value of TOBT cannot be determined, i.e. the departure cannot be included in departure sequence!

• EOBT – Estimated Off-Block Time is an estimation when taxi (or pushback) will be commenced. EOBT becomes automatically part of A-CDM system by filing FPL. It is the time stated in box 13 in standard ICAO FPL form. In order to state EOBT correctly, SOBT value must be known!
• TOBT - Target Off-Block Time represents the moment when the ground handling should be finished and the aircraft is fully ready to commence start-up (pushback), i.e. all doors and service entries are closed and the crew monitors appropriate frequency for start-up approval. TOBT is therefore a qualified estimation of the earliest occurrence of such situation. TOBT is a basic input for TSAT calculation.

TOBT input is possible only after the FPL is filed and approved!

• TSAT – Target Start-up Approval Time represents qualified estimation when the start-up (pushback) is expected. Its goal is to determine the departure sequence for take-off in such a way, that all requirements for efficient airspace management are fulfilled, taxi times are minimized and the progress of ground handling is taken into account. Therefore depending on intensity of departing traffic the value of allocated TSAT to one particular flight may be considerably later than its TOBT. Compliance with TSAT tolerance by flight crews results in maximum utilization of runway capacity. TSAT tolerance at LKPR is ±5 minutes from its value.
• AOP – Airport Operations Plan evaluates available capacity of airport resources (e.g. aircraft stands). It consists mainly of the flight schedule for a given day including expected aircraft types, number of passengers and planned resources allocation for individual flights.